1. Field of Invention The techniques described herein relate generally to reducing artifacts in digital images, and more particularly to reducing ringing and halo artifacts in digital images.
2. Discussion of the Related Art
Digital image and video processing may occur in many different types of devices, including set-top boxes for cable television, televisions, cameras, videocameras, DVD players, DVD recorders, and computers. Some of these devices may create and store digital images and video, for example, by taking a picture with a digital camera. Other devices may take stored digital images and video and present them to a person on a screen, such as a computer.
The processing of digital images and video may cause undesirable artifacts to appear in the images and video. For example, in some situations, the encoding of digital images or video may cause ringing artifacts. In other situations, the resealing of digital images or video may also cause ringing artifacts. Ringing artifacts are artifacts that may appear near edges of an image and appear as concentric rings or adjacent lines emanating away from an edge.
In certain applications, digital images and video may be processed to enhance their appearance. One example is processing digital images or video by a process called “peaking” to enhance the appearance of images and video by making the edges clearer. The processing of images and video, for example by peaking, may also create undesirable artifacts. One undesirable artifact is the amplification of ringing artifacts. Another undesirable artifact is the appearance of excessive overshoot and undershoot adjacent to edges in an image, which may create a “halo” effect.
Artifacts in images and video, such as ringing artifacts and a halo effect, may be undesirable, and the appearance of images and video may be improved by controlling these artifacts.